Microsoft today announced a partnership with Corona Labs, the maker of the Corona SDK for cross-platform app development, which will enable Corona SDK developers to build apps for Windows Phone 8 and Windows 8. Beta support for Windows Phone 8 will be available in the first quarter of 2014.

The two companies say full support for Windows Phone 8 and Windows 8 will follow. Unfortunately, neither company would disclose what date, let alone the month they are aiming for (all we were told is “the first half of 2014″).

Corona says it already has over 300,000 developers worldwide publishing apps for Android, iOS, Kindle, and NOOK with a single code base. Today’s announcement means these app builders can also bring their work to Windows Phone 8 and Windows 8 without modifying their existing code.

Unsurprisingly, both Microsoft and Corona Labs are pleased with the move.

“We continue to see strong growth within the Windows app ecosystem, thanks in part to contributions from companies like Corona Labs,” Todd Brix, Microsoft’s general manager of Windows Apps and Store, said in a statement. “Corona’s platform has attracted a large number of successful developers who will be able to easily extend their apps into the Windows ecosystem.”

“Windows Phone 8 and Windows 8 have proven to be great platforms for developers, and their growing user base presents a growing opportunity,” Corona Labs COO David Rangel said in a statement. “We look forward to working with Microsoft, empowering Corona developers to build apps for Windows devices and reach an even broader audience for their apps and games.”

The Corona SDK helps developers build 2D apps across multiple platforms with speed; the company says it helps make app building up to 10 times faster than regular processes. To what extent this is true or not doesn’t really matter; what’s important for Microsoft here is to continue building out its app developer community.

300,000 developers is a decent number by which to grow your potential developer base. Corona Labs is just one of many stepping stones on Microsoft’s bigger quest to cement its status as the third mobile platform.

Emil was a reporter for The Next Web between 2012 and 2014. Over the years, he has covered the tech industry for multiple publications, including Ars Technica, Neowin, TechSpot, ZDNet, and CNET. Stay in touch via Facebook, Twitter, and Google+.